Portions of this disclosure are described in terms of, e.g., encoded signals for digital designs, product packaging (sometimes just referred to herein as “packaging” or “package”) and other objects. These encoding techniques can be used, e.g., to alter or transform how color inks are printed on various physical substrates. The alterations or transformations preferably result in a printed design carrying machine-readable indicia on a surface of a physical object.
Various forms of signal encoding (or “embedding”) include, e.g., “steganographic encoding” and “digital watermarking.” Digital watermarking is a process for transforming physical or electronic media to embed a machine-readable code (or “auxiliary data”) into the media. In some cases the media is modified such that the embedded code is obscured, yet may be detected through an automated detection process. Digital watermarking is often applied to electronic or physical objects such as printed objects, images, audio signals, and video signals. However, it may also be applied to other types of objects, including, e.g., product packaging, electronics such as circuit boards and CPUs, stickers, logos, product hang tags, line-art, software, multi-dimensional graphics models, and surface textures of such objects.
In this document we use the terms “digital watermark” and “watermark” (and various forms thereof) interchangeably.
Auxiliary data embedding systems typically include two components: an encoder (or embedder) that embeds the auxiliary signal in a host image or object, and a decoder (or detector) that detects and reads the embedded auxiliary signal from the host image or object. The encoder may embed the auxiliary signal by altering or transforming a host image or object to carry the auxiliary data. The detection component analyzes a suspect image, object or signal to detect whether an auxiliary signal is present, and if so, extracts or reads information carried in it.
Several particular digital watermarking and auxiliary data embedding techniques have been developed. The reader is presumed to be familiar with the literature in this field. Particular techniques for embedding and detecting imperceptible digital watermarks are detailed in the assignee's patent documents including U.S. Pat. Nos. 7,054,461, 7,286,685, 9,129,277, 9,380,186, 9,401,001 and 9,449,357, U.S. patent application Ser. No. 14/725,399 (published as US 2016-0275639 A1), Ser. No. 14/724,729 (published as US 2016-0217547 A1), and Ser. No. 14/842,575, filed Sep. 1, 2015 (U.S. Pat. No. 9,819,950); and International Application No. PCT/US2015/44904, filed Aug. 12, 2015 (published as WO 2016025631 A1). Related technology is detailed in Assignee's U.S. patent application Ser. No. 15/073,483 (published as US 2016-0275326 A1). Each of the patent documents mentioned in this paragraph are hereby incorporated herein by reference in its entirety, including all drawings and any appendices.
One aspect of the disclosure is a digital watermark embedding apparatus. The apparatus includes: memory for storing data representing a digital image; one or more processors configured for transforming the data by embedding a digital watermark therein, the digital watermark comprising a synchronization component and a message component; one or more processors configured for: attacking the transformed data to yield altered, transformed data; analyzing the altered, transformed data to obtain detectability measures therefrom, a first detectability measure comprising a measure corresponding to the synchronization component strength, and a second measure comprising a measure corresponding to the message component strength; and based on a combination of the first detectability measure and the second detectability measure, predicting —along one or more swipe paths—a likelihood that the transformed data, once printed on a physical substrate, will be detectable from optical scan data representing such.
The synchronization component may include a plurality of peaks in a transform domain, and the first detectability measure comprises a measure representing such peaks relative to their neighborhood. The message component may include a signature, and the second detectability measure comprises a relationship between embedded information and detected information.
The embedding apparatus may further include a re-embedding module that is activated when the predicted likelihood falls below a predetermined level, the re-embedding module further transforming the transformed data to increase digital watermark strength or coverage area.
The embedding apparatus may further include a mapping module, the mapping module configured to generate a multi-color map which represents watermark detection of the transformed data. The multi-color map may include probability indicators for the one or more swipe paths.
Another aspect of the disclosure is an apparatus comprising: a display; memory for storing data representing a digital image; one or more processors configured for transforming the data by embedding digital watermarking therein, the digital watermarking comprising a synchronization component and a message component; one or more processors configured for attacking the transformed data to yield altered, transformed data; means for analyzing the altered, transformed data to obtain detectability measures therefrom, a first detectability measure comprising a measure corresponding to the synchronization component strength, and a second measure comprising a measure corresponding to the message component strength; means for predicting, based on a combination of the first detectability measure and the second detectability measure, a likelihood that the transformed data, once printed on a physical substrate, will be detectable from optical scan data representing such, such likelihoods being predicted along one or more swipe paths; and a graphical user interface for causing said display to display a multi-color map which represents watermark detection of the transformed data. The multi-color map may include probability indicators for the one or more swipe paths.
In one example, the means for analyzing and the means for predicting comprise one or more application specific integrated circuits (ASIC). In another example, the means for analyzing and the means for predicting comprise one or more specifically configured electronic processors. Of course, other examples are evident from the following description.
In still another aspect, a system is described to include: memory for storing data representing a color image; one or more processors configured for: transforming the data by embedding digital watermarking therein; analyzing the transformed data to obtain detectability measures therefrom, and generating a signal detection robustness map using the detectability measures, the robustness map visually indicating areas having more detectability capability and areas having relatively less detectability capability of the digital watermarking; and masking the color image with the robustness map to yield a final robustness image, the final robustness image comprising original color information corresponding to image areas having detectability capability and greyscale information corresponding to image areas having relatively less detectability capability.
Yet another aspect described is a method comprising: obtaining a digital watermarked color image; converting the digital watermarked color image to greyscale, said converting yields a greyscale image; modifying the greyscale image's opacity to a percentage less than 100% opacity, said modifying yielding a modified greyscale image; overlaying the modified greyscale image onto a white or light background; masking the digital watermarked color image with a robustness map, the robustness map indicating detectability of the digital watermarking per image pixel or groups of image pixels, said masking yielding a masked color image; overlaying the masked color image on top of the modified greyscale image to yield a final robustness image, in which the final robustness image comprises original design colors of the digital watermarked color image for those image areas having a higher probability of digital watermark detection and comprises grey information for those image areas having a relatively lower probability of the digital watermark being detected; and displaying the final robustness image on a computer monitor or display including displaying original design colors and grey.
Another aspect is an image processing method including: obtaining an image comprising a plurality of color separations or channels, in which the image comprises at least a 1D or 2D barcode represented therein and plural encoded signals encoded therein, the 1D or 2D barcode comprising a first plural-bit code and the plural encoded signals comprising a second plural-bit code; first analyzing data representing the image to decode the 1D or 2D barcode, said first analyzing yield the first plural-bit code; for each of the plurality of color separations or channels, second analyzing data representing the image to decode the encoded signal, said second analyzing yielding plural instances of the second plural-bit code; determining whether the plural instances of the second plural-bit code conflict with the first plural-bit code; for each conflict, providing information associated with a spatial location of the conflict relative to the image.
In the image processing method the “obtaining” may occur prior to a printing plate manufacture process.
In the image processing method the first analyzing data representing the image to decode the 1D or 2D barcode may operate on nonadjacent scanline data from the image.
In the image processing method, prior to the second analyzing, the method may include segmenting at least a portion of the image into a plurality of blocks, in which the second analyzing operates on individual blocks from the plurality of blocks for each of the separations or channels.
In the image processing method, the first plural bit code and the second plural bit code may include data representing a UPC code or a GTIN code.
In the image processing method, the information associated with the spatial location may be formatted as a conflict map, where the conflict map includes a graphical box or highlight for a spatial location of the conflict relative to the image.
Another aspect of the disclosure is an image processing apparatus including: electronic memory for storing an image, the image comprising a plurality of color separations or channels, in which the image comprises at least a 1D or 2D barcode represented therein and an encoded signal encoded therein, the 1D or 2D barcode comprising a first plural bit code and the encoded signal comprising a second plural bit code; a barcode module configured for analyzing data representing the image to decode the 1D or 2D barcode to obtain the first plural bit code; a decoder module configured for analyzing each of the plurality of color separations or channels to decode the encoded signal to obtain the second plural bit code; a comparator module configured for comparing the second plural bit code with the first plural bit code for a conflict; and a results module configured for producing a conflict map, the conflict map comprising an identification of a conflict, and a spatial location of the conflict relative to the image.
Yet another aspect of the disclosure is a method of detecting printing plate misuse, on a printing press having a plurality of printing plates configured to carry an encoded signal. The method includes: obtaining a verification icon comprising a plurality of design elements, with a first design element carried in a Cyan (C) color channel, a second design element carried in Magenta (M) color channel, a third design element carried in a Yellow (Y) color channel and a forth design element carried in a Black (K) color channel, the first design element, second design element, third design element and forth design element, cooperating when printing to produce the verification icon; obtaining Cyan, Magenta, Yellow and Black printing plates; using the printing plates, printing the verification icon on a substrate to yield a printed verification icon; and evaluating the printed verification icon to determine if an orientation of the first design element, second design element, third design element and forth design element comprise a predetermined orientation arrangement, in which a deviation from the predetermined orientation arrangement indicates a printing plate misuse or reuse.
Still another aspect of the disclosure is a method including: providing a verification icon, the verification icon comprising a plurality of design elements, with a first design element carried in a Cyan (C) color channel, a second design element carried in Magenta (M) color channel, a third design element carried in a Yellow (Y) color channel and a forth design element carried in a Black (K) color channel, the first design element, second design element, third design element and forth design element contributing to the verification icon; assigning a first orientation of the verification icon to a first product family member; assigning a second orientation of the verification icon to a second product family member; assigning a third orientation of the verification icon to a third product family member; assigning a forth orientation of the verification icon to a forth product family member; from a verification icon printed on a white substrate, determining a printing plate misuse or reuse based on an orientation of at least one of the first design element, second design element, third design element or forth design element.
Another aspect includes a method of determining a printing plate inconsistency. The method includes: generating a pseudo-random noise pattern; representing the pseudo-random noise pattern in a first set of color channels through modifying data representing the first set of color channels, in which the modifying introduces a first modification polarity in each color channel of the first set of color channels; representing the pseudo-random noise pattern in a black color channel through modifying data representing the black color channel, in which the modifying introduces a second modification polarity in the black color channel that is inversely related to the polarity of the first modification polarity; spatially aligning the pseudo-random noise pattern in the first set of color channels and the pseudo-random noise pattern in a black color channel such that luminance or chrominance attributable to the pseudo-random noise pattern in the first set of color channels offsets or reduces luminance or chrominance attributable to the pseudo-random noise pattern in a black color channel, in which the spatial aligning in is the form of text or a 1D or 2D symbology.
Another aspect is method of monitoring a spectral difference between a substrate and one or more colors, the one or more colors configured to carry an encoded signal. The method includes: determining a minimum ink value and a maximum ink value of an encoded signal carrier; determining a spectral reflectance difference at or around 660 nm between: i) the substrate without any ink and the minimum ink value, and ii) the substrate without any ink and the maximum ink value; based on the difference of i and ii, determining a tolerance range; printing the minimum ink value and the maximum ink value in a control strip area; measuring the spectral reflectance of the substrate, the printed minimum ink and the printed maximum ink to yield measurements, and using the measurements to determine whether the printing press is maintaining printing within the determining tolerance range.
Yet another aspect of the disclosure is an image processing method for detecting printing plates or print design layers inconsistency. The method includes: obtaining spectral reflectance data corresponding to a printed verification logo, the spectral reflectance data captured with a spectrophotometer, in which the verification logo is printed on a substrate having a first color, and in which the verification logo comprises a plurality of design elements, with a first design element carried in a second color channel, a second design element carried in a third color channel, a third design element carried in a fourth color channel, the first design element, second design element and third design element contributing to the verification logo, and in which the substrate comprises an encoded signal printed thereon, the encoded signal comprising a plural-bit payload; obtaining expected colors associated with the verification logo; determining how the spectral reflectance data corresponds to the expected colors, said determining yielding a determination; based on the determination, generating a response associated with the printing plates or print design layers.
In one implementation, the spectrophotometer comprises a component of a closed-loop press monitoring system.
In another implementation, the expected colors are obtained from spectral reflectance data associated with a control strip printed on the substrate.
In still another implementation, the determining determines that the spectral reflectance data corresponds to the first color, and the determination indicates printing plates or print design layers inconsistency. In this case, response may include a signal indicating the printing plates or print design layers inconsistency
In another implementation, the spectral reflectance data corresponds with an overprint of the first design element and the second design element or the third design element, and the determination indicates printing plates or print design layers inconsistency. In this case, the response may include a signal indicating the printing plates or print design layers inconsistency.
In a related implementation, the plural-bit payload comprises data associated with the expected colors.
In another implementation, the spectral reflectance data corresponding to the printed verification logo comprises data corresponding to a plurality of samples. In this case, the plurality of samples may comprise scanline data. In a related case, the determining considers spectral reflectance data associated with each of the plurality of samples.
Further aspects, features and advantages will become even more apparent with reference to the following detailed description and accompanying drawings.